Surveyor sight

ABSTRACT

Sighting apparatus, usable in surveying, comprises a base and a first support therefor; a standard to support a rod or target and mounted on the base to extend upright directly above the first support; second and third supports including a pair of elongated legs having adjustable pivotal attachment to the base accommodating relative swinging of the legs through wide, generally horizontally extending arcs; and, level indicator means on the base to indicate when the standard extends vertically.

Umted States Patent [151 3, Haun 1 Aug. 22, 1972 [54] SURVEYOR SIGHT 2,788,578 4/1957 Digiacinto ..33/74 R 72 Inventor: Horace H. Haun, 9240 Burke St., igggggg 2133; 8x5 32 33 P Vera C 90660 2,806,670 9/1957 Straster ..248/46 x [22] Filed: June 19, 1970 2,843,347 7/1958 King ..33/74 D X 21 A l. l 1 PP No 47,811 Primary ExaminerR0brt B. Hull Attorney-White, Haefliger and Bachand [52] US. Cl ..33/295, 40/125 H, 248/170,

51 I Cl 248/188.4 [57] ABSIRA CT t. E Fgeld of Search. 40/40 39 125 Sighting apparatus, usable in surveying, comprises a 248/170 'g' 313/74 74 B base and a first support therefor; a standard to support 74 a rod or target and mounted on the base to extend upright directly above the first support; second and third supports including a pair .of elongated legs hav- [56] References Cited ing adjustable pivotal attachment to the base accom- UNITED STATES PATENTS g g a y z g g 3; h legs g g q gener y onzont y exten mg arcs; an eve m- 3,l99,209 8/1965 Bergqulst ..33/74 R X dicator means on the base to indicate when the stan 3,173,642 3/ 1965 Greenspan ..248/170 dard extends venicany 3,292,569 12/1966 Trigilio ..40/39 X 2,238,708 4/ 1941 Russell ..248/ 188.7 7 Claims, 5 Drawing Figures SURVEYOR SIGHT BACKGROUND OF THE INVENTION This invention relates generally to surveying apparatus, and more particularly concerns improvements in surveyors sighting equipment.

In establishing grades and angles the surveyor commonly uses sighting equipment such as a transit at one location and a sighting rod at a distant location. For high accuracy, the rod must be held or mounted so as to extend precisely vertically, which presents a problem where the terrain is uneven and the rod must be maintained vertically over a considerably length of time. While attempts have been made in the past to solve this problem, no one to my knowledge has provided a sight having the unusually advantageous, simple and effective structure, function and results characterized by the present invention.

SUMMARY OF THE INVENTION Basically, the invention-is embodied in sighting apparatus that comprises a base and a first support therefor; a standard mounted on the base to extend upright directly above the first support; second and third supports including a pair of elongated legs having adjustable pivotal attachment to the base accommodating relative swinging of the legs through wide generally horizontally extending arcs; and, level indicator means on the base to indicate when the standard extends vertically. As will be seen such elongated legs may be swung to a large number of positions and relative to one another and to the first support, to accommodate precise and rapid adjustment of the standard to vertical position even though the terrain is quite rough. In this regard, the second and third supports may include upright elements having vertically adjustable attachment to the legs to project therebelow for ground engagement.

Other objects and advantages include the provision of a level indicator in the form of a bubble chamber on the base mounting the standard; the provision of a first support and standard in the form of a shaft having vertically adjustable attachment to the base and projecting therefrom; the provision of sighting structure on the standard, as for example a rotary light reflector; and

the mounting of the legs to the base to have a range of alternate positions within a swing-arc of at least about 75, as will appear.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:

DRAWING DESCRIPTION FIG. 1 is a perspective showing of a surveyors sight incorporating the invention;

FIG. 2 is an enlarged vertical section taken on line 2--2 of FIG. 1;

FIG. 3 is a plan view of the FIG. 1 sight with legs collapsed;

FIG. 4 is a view similar to FIG. 3, showing the sight with legs fully extended; and

FIG. 5 is a view like FIG. 1 showing a modified sight.

2 DETAILED DESCRIPTION In the drawing, the base 10 of the overall apparatus 1 1 may advantageously include upper and lower metal plates 12 and 13 attached to an intermediate block 20, as by means of fasteners 14. A space 15 is left between the plates and beyond the edge 16 of the block, for purposes as will appear. Another fastener l4a extends between the cantilevered extents of the plates 12 and 13, for adjustment purposes as will also appear.

A standard is mounted on the base to extend upright, the illustrated standard 17 being in the form of a shaft received downwardly in a bore 18 in the base to be adjustably clamped by the set screw 19 threaded into block 20. The upper extent of the standard may be striped at 21, for sighting purposes.

A first support for the base may take the form of a stub shaft 22 having a tapered lower terminal 22a to be placed directly onto the center point on the top of a monument 23 or other object, the axis 24 of the standard 17 then passing through that center point. Shaft 22 has vertically adjustableattachment to the base at 22b. Also located on the base is what may be referred v to as level indicator means, as for example a bubble chamber 25. The center 26 of the latter is nearly equidistant from the axis 24 and vertical axes of pivot pins 28 and 29 to be described. The chamber base 25a is attached to the plate 12 by three adjustable screws 40, and urged upwardly by springs 41. Thus, the bubble in the chamber may be precisely centered when a plumb bob is used to orient the standard 17 vertically.

Also provided are second and third supports including a pair of elongated legs, such as at 30 and 31, having adjustable pivotal attachment, as via pins 28 and 29, to the base 10 accommodating relative swinging of the legs through wide generally horizontally extending arcs. Thus, for example, each leg has a range of alternate positions within a swing-arc of at least about and preferably up to as is clear from a comparison of FIGS. 3 and 4. Therefore, the support leg adjustment enables use of the device under rough and sloping terrain-conditions, to provide precise vertical orientation of the standard.

The second and third supports may also advantageously include upright elements, such as screws 32 and 33, having vertically adjustable attachment to the outer portions of the legs 30 and 31. The screws project below the legs for ground engagement, contributing further to accommodation of the device to use on rough or sloping terrain. Screw terminals 32a and 33a are manually adjustable.

Once the legs have been horizontally adjusted and the screws vertically adjusted to achieve a vertical orientation of the standard, the fastener 14a may be tightened to cause the cantilevered portions of the plates 12 and 13 to clamp opposite sides of the legs rigidly to the base, as may be desired by the user. Note that the legs pivot on pins 28 and 29 received in vertical bores 34 in plate 13. Also, friction between the legs 30 and 31 and plates 12 and 13 may be varied by means of adjustment of fastener 14a FIG. 5 illustrates a modified apparatus wherein the sighting structure includes a vertical standard 17a on which a rotary light reflector is mounted. The reflector v50 may include a pair of oppositely facing parabolic reflectors 51 carried at 52 on a vertical pivot pin 53 freely rotatable on the standard in response to wind induced rotation of the reflector. A beam of light directed at the reflector will then be reflected in pulses as the reflectors rotate. Otherwise, the FIG. 5 apparatus is the same in FIGS. 1-4.

I CLAIM:

1. Surveyors sighting apparatus, comprising a. a base and a first support therefor,

b. a standard mounted on the base to extend upright, said support defined by a shaft projecting below the base-directly beneath the standard and having vertically adjustable attachment to the base,

c. second and third supports including a pair of elongated legs having adjustable pivotal attachment to the base accommodating relative swinging of the legs through wide generally horizontally extending arcs, and

d. level indicator means on the base to indicate when the standard extends vertically.

2. The combination of claim 1 wherein said second and third supports include upright elements having ver- 3. The combination of claim 1 wherein said level in- I dicator means comprises a bubble chamber.

4. The combination of claim 1 including sighting structure on the standard.

5. The combination of claim 4 wherein said sighting structure includes a rotary light reflector.

6. The combination of claim 1 wherein each of the legs has a range of alternate positions within a swingarc of at least about 7. The combination of claim 1 wherein the base comprises upper and lower plates between which the inner ends of the legs extend, and means to adjustably clamp the plates to said inner ends, the upper plate having a vertical bore in which the lower end of the standard projects, and means to releasably clamp the lower end of the standard projecting downwardly relative to the upper plate. 

1. Surveyor''s sighting apparatus, comprising a. a base and a first support therefor, b. a standard mounted on the base to extend upright, said support defined by a shaft projecting Below the base directly beneath the standard and having vertically adjustable attachment to the base, c. second and third supports including a pair of elongated legs having adjustable pivotal attachment to the base accommodating relative swinging of the legs through wide generally horizontally extending arcs, and d. level indicator means on the base to indicate when the standard extends vertically.
 2. The combination of claim 1 wherein said second and third supports include upright elements having vertically adjustable attachment to the legs to project therebelow for ground engagement.
 3. The combination of claim 1 wherein said level indicator means comprises a bubble chamber.
 4. The combination of claim 1 including sighting structure on the standard.
 5. The combination of claim 4 wherein said sighting structure includes a rotary light reflector.
 6. The combination of claim 1 wherein each of the legs has a range of alternate positions within a swing-arc of at least about 75* .
 7. The combination of claim 1 wherein the base comprises upper and lower plates between which the inner ends of the legs extend, and means to adjustably clamp the plates to said inner ends, the upper plate having a vertical bore in which the lower end of the standard projects, and means to releasably clamp the lower end of the standard projecting downwardly relative to the upper plate. 